fs/fscache/internal.h

   1 /* Internal definitions for FS-Cache
   2  *
   3  * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 /*
  13  * Lock order, in the order in which multiple locks should be obtained:
  14  * - fscache_addremove_sem
  15  * - cookie->lock
  16  * - cookie->parent->lock
  17  * - cache->object_list_lock
  18  * - object->lock
  19  * - object->parent->lock
  20  * - fscache_thread_lock
  21  *
  22  */
  23
  24 #include <linux/fscache-cache.h>
  25 #include <linux/sched.h>
  26
  27 #define FSCACHE_MIN_THREADS     4
  28 #define FSCACHE_MAX_THREADS     32
  29
  30 /*
  31  * fsc-cache.c
  32  */
  33 extern struct list_head fscache_cache_list;
  34 extern struct rw_semaphore fscache_addremove_sem;
  35
  36 extern struct fscache_cache *fscache_select_cache_for_object(
  37         struct fscache_cookie *);
  38
  39 /*
  40  * fsc-cookie.c
  41  */
  42 extern struct kmem_cache *fscache_cookie_jar;
  43
  44 extern void fscache_cookie_init_once(void *);
  45 extern void __fscache_cookie_put(struct fscache_cookie *);
  46
  47 /*
  48  * fsc-fsdef.c
  49  */
  50 extern struct fscache_cookie fscache_fsdef_index;
  51 extern struct fscache_cookie_def fscache_fsdef_netfs_def;
  52
  53 /*
  54  * fsc-histogram.c
  55  */
  56 #ifdef CONFIG_FSCACHE_HISTOGRAM
  57 extern atomic_t fscache_obj_instantiate_histogram[HZ];
  58 extern atomic_t fscache_objs_histogram[HZ];
  59 extern atomic_t fscache_ops_histogram[HZ];
  60 extern atomic_t fscache_retrieval_delay_histogram[HZ];
  61 extern atomic_t fscache_retrieval_histogram[HZ];
  62
  63 static inline void fscache_hist(atomic_t histogram[], unsigned long start_jif)
  64 {
  65         unsigned long jif = jiffies - start_jif;
  66         if (jif >= HZ)
  67                 jif = HZ - 1;
  68         atomic_inc(&histogram[jif]);
  69 }
  70
  71 extern const struct file_operations fscache_histogram_fops;
  72
  73 #else
  74 #define fscache_hist(hist, start_jif) do {} while (0)
  75 #endif
  76
  77 /*
  78  * fsc-main.c
  79  */
  80 extern unsigned fscache_defer_lookup;
  81 extern unsigned fscache_defer_create;
  82 extern unsigned fscache_debug;
  83 extern struct kobject *fscache_root;
  84
  85 extern int fscache_wait_bit(void *);
  86 extern int fscache_wait_bit_interruptible(void *);
  87
  88 /*
  89  * fsc-proc.c
  90  */
  91 #ifdef CONFIG_PROC_FS
  92 extern int __init fscache_proc_init(void);
  93 extern void fscache_proc_cleanup(void);
  94 #else
  95 #define fscache_proc_init()     (0)
  96 #define fscache_proc_cleanup()  do {} while (0)
  97 #endif
  98
  99 /*
 100  * fsc-stats.c
 101  */
 102 #ifdef CONFIG_FSCACHE_STATS
 103 extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS];
 104 extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS];
 105
 106 extern atomic_t fscache_n_op_pend;
 107 extern atomic_t fscache_n_op_run;
 108 extern atomic_t fscache_n_op_enqueue;
 109 extern atomic_t fscache_n_op_deferred_release;
 110 extern atomic_t fscache_n_op_release;
 111 extern atomic_t fscache_n_op_gc;
 112
 113 extern atomic_t fscache_n_attr_changed;
 114 extern atomic_t fscache_n_attr_changed_ok;
 115 extern atomic_t fscache_n_attr_changed_nobufs;
 116 extern atomic_t fscache_n_attr_changed_nomem;
 117 extern atomic_t fscache_n_attr_changed_calls;
 118
 119 extern atomic_t fscache_n_allocs;
 120 extern atomic_t fscache_n_allocs_ok;
 121 extern atomic_t fscache_n_allocs_wait;
 122 extern atomic_t fscache_n_allocs_nobufs;
 123 extern atomic_t fscache_n_alloc_ops;
 124 extern atomic_t fscache_n_alloc_op_waits;
 125
 126 extern atomic_t fscache_n_retrievals;
 127 extern atomic_t fscache_n_retrievals_ok;
 128 extern atomic_t fscache_n_retrievals_wait;
 129 extern atomic_t fscache_n_retrievals_nodata;
 130 extern atomic_t fscache_n_retrievals_nobufs;
 131 extern atomic_t fscache_n_retrievals_intr;
 132 extern atomic_t fscache_n_retrievals_nomem;
 133 extern atomic_t fscache_n_retrieval_ops;
 134 extern atomic_t fscache_n_retrieval_op_waits;
 135
 136 extern atomic_t fscache_n_stores;
 137 extern atomic_t fscache_n_stores_ok;
 138 extern atomic_t fscache_n_stores_again;
 139 extern atomic_t fscache_n_stores_nobufs;
 140 extern atomic_t fscache_n_stores_oom;
 141 extern atomic_t fscache_n_store_ops;
 142 extern atomic_t fscache_n_store_calls;
 143
 144 extern atomic_t fscache_n_marks;
 145 extern atomic_t fscache_n_uncaches;
 146
 147 extern atomic_t fscache_n_acquires;
 148 extern atomic_t fscache_n_acquires_null;
 149 extern atomic_t fscache_n_acquires_no_cache;
 150 extern atomic_t fscache_n_acquires_ok;
 151 extern atomic_t fscache_n_acquires_nobufs;
 152 extern atomic_t fscache_n_acquires_oom;
 153
 154 extern atomic_t fscache_n_updates;
 155 extern atomic_t fscache_n_updates_null;
 156 extern atomic_t fscache_n_updates_run;
 157
 158 extern atomic_t fscache_n_relinquishes;
 159 extern atomic_t fscache_n_relinquishes_null;
 160 extern atomic_t fscache_n_relinquishes_waitcrt;
 161
 162 extern atomic_t fscache_n_cookie_index;
 163 extern atomic_t fscache_n_cookie_data;
 164 extern atomic_t fscache_n_cookie_special;
 165
 166 extern atomic_t fscache_n_object_alloc;
 167 extern atomic_t fscache_n_object_no_alloc;
 168 extern atomic_t fscache_n_object_lookups;
 169 extern atomic_t fscache_n_object_lookups_negative;
 170 extern atomic_t fscache_n_object_lookups_positive;
 171 extern atomic_t fscache_n_object_created;
 172 extern atomic_t fscache_n_object_avail;
 173 extern atomic_t fscache_n_object_dead;
 174
 175 extern atomic_t fscache_n_checkaux_none;
 176 extern atomic_t fscache_n_checkaux_okay;
 177 extern atomic_t fscache_n_checkaux_update;
 178 extern atomic_t fscache_n_checkaux_obsolete;
 179
 180 static inline void fscache_stat(atomic_t *stat)
 181 {
 182         atomic_inc(stat);
 183 }
 184
 185 extern const struct file_operations fscache_stats_fops;
 186 #else
 187
 188 #define fscache_stat(stat) do {} while (0)
 189 #endif
 190
 191 /*
 192  * raise an event on an object
 193  * - if the event is not masked for that object, then the object is
 194  *   queued for attention by the thread pool.
 195  */
 196 static inline void fscache_raise_event(struct fscache_object *object,
 197                                        unsigned event)
 198 {
 199         BUG();  // TODO
 200 }
 201
 202 /*****************************************************************************/
 203 /*
 204  * debug tracing
 205  */
 206 #define dbgprintk(FMT, ...) \
 207         printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
 208
 209 /* make sure we maintain the format strings, even when debugging is disabled */
 210 static inline __attribute__((format(printf, 1, 2)))
 211 void _dbprintk(const char *fmt, ...)
 212 {
 213 }
 214
 215 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
 216 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
 217 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
 218
 219 #define kjournal(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__)
 220
 221 #ifdef __KDEBUG
 222 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
 223 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
 224 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
 225
 226 #elif defined(CONFIG_FSCACHE_DEBUG)
 227 #define _enter(FMT, ...)                        \
 228 do {                                            \
 229         if (__do_kdebug(ENTER))                 \
 230                 kenter(FMT, ##__VA_ARGS__);     \
 231 } while (0)
 232
 233 #define _leave(FMT, ...)                        \
 234 do {                                            \
 235         if (__do_kdebug(LEAVE))                 \
 236                 kleave(FMT, ##__VA_ARGS__);     \
 237 } while (0)
 238
 239 #define _debug(FMT, ...)                        \
 240 do {                                            \
 241         if (__do_kdebug(DEBUG))                 \
 242                 kdebug(FMT, ##__VA_ARGS__);     \
 243 } while (0)
 244
 245 #else
 246 #define _enter(FMT, ...) _dbprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
 247 #define _leave(FMT, ...) _dbprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
 248 #define _debug(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__)
 249 #endif
 250
 251 /*
 252  * determine whether a particular optional debugging point should be logged
 253  * - we need to go through three steps to persuade cpp to correctly join the
 254  *   shorthand in FSCACHE_DEBUG_LEVEL with its prefix
 255  */
 256 #define ____do_kdebug(LEVEL, POINT) \
 257         unlikely((fscache_debug & \
 258                   (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
 259 #define ___do_kdebug(LEVEL, POINT) \
 260         ____do_kdebug(LEVEL, POINT)
 261 #define __do_kdebug(POINT) \
 262         ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)
 263
 264 #define FSCACHE_DEBUG_CACHE     0
 265 #define FSCACHE_DEBUG_COOKIE    1
 266 #define FSCACHE_DEBUG_PAGE      2
 267 #define FSCACHE_DEBUG_OPERATION 3
 268
 269 #define FSCACHE_POINT_ENTER     1
 270 #define FSCACHE_POINT_LEAVE     2
 271 #define FSCACHE_POINT_DEBUG     4
 272
 273 #ifndef FSCACHE_DEBUG_LEVEL
 274 #define FSCACHE_DEBUG_LEVEL CACHE
 275 #endif
 276
 277 /*
 278  * assertions
 279  */
 280 #if 1 /* defined(__KDEBUGALL) */
 281
 282 #define ASSERT(X)                                                       \
 283 do {                                                                    \
 284         if (unlikely(!(X))) {                                           \
 285                 printk(KERN_ERR "\n");                                  \
 286                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 287                 BUG();                                                  \
 288         }                                                               \
 289 } while (0)
 290
 291 #define ASSERTCMP(X, OP, Y)                                             \
 292 do {                                                                    \
 293         if (unlikely(!((X) OP (Y)))) {                                  \
 294                 printk(KERN_ERR "\n");                                  \
 295                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 296                 printk(KERN_ERR "%lx " #OP " %lx is false\n",           \
 297                        (unsigned long)(X), (unsigned long)(Y));         \
 298                 BUG();                                                  \
 299         }                                                               \
 300 } while (0)
 301
 302 #define ASSERTIF(C, X)                                                  \
 303 do {                                                                    \
 304         if (unlikely((C) && !(X))) {                                    \
 305                 printk(KERN_ERR "\n");                                  \
 306                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 307                 BUG();                                                  \
 308         }                                                               \
 309 } while (0)
 310
 311 #define ASSERTIFCMP(C, X, OP, Y)                                        \
 312 do {                                                                    \
 313         if (unlikely((C) && !((X) OP (Y)))) {                           \
 314                 printk(KERN_ERR "\n");                                  \
 315                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 316                 printk(KERN_ERR "%lx " #OP " %lx is false\n",           \
 317                        (unsigned long)(X), (unsigned long)(Y));         \
 318                 BUG();                                                  \
 319         }                                                               \
 320 } while (0)
 321
 322 #else
 323
 324 #define ASSERT(X)                       do {} while (0)
 325 #define ASSERTCMP(X, OP, Y)             do {} while (0)
 326 #define ASSERTIF(C, X)                  do {} while (0)
 327 #define ASSERTIFCMP(C, X, OP, Y)        do {} while (0)
 328
 329 #endif /* assert or not */